The present invention relates to improvements in compact cases for cosmetic preparations and, particularly, to a new and improved compact case providing an airtight seal to prevent product dryout and seepage.
Compact cases have long been used for enclosing various cosmetic preparations such as powder, rouge, blushers, facial creams, and the like. Such cases are generally small portable containers designed to fit in a woman's pocketbook or purse. A problem with such compact cases has been their general inability to prevent dryout, caking, or seepage of the cosmetic preparation. The problem is exemplified by the patents to Fullmer U.S. Pat. No. 1,912,187 to Sandberg U.S. Pat. No. 2,054,004 to Leitner U.S. Pat. No. 2,410,585 and to Grassi U.S. Pat. No. 2,424,817. Each of these patents discloses a construction which attempts to avoid the above problems. Fullmer discloses a ring of cork, felt, or other compressible material to provide a seal and prevent the spilling of powder when the compact is closed. Sandberg discloses springs to hold an upper edge of the powder receptacle against an inner cover when an outer cover was closed. Leitner discloses a toroidal compressible gasket or sealing ring, permanently seated in a circular groove to be compressed to form a more positive seal when the two casing members are fully closed. Grassi discloses a pair of rings which have mutually engageable metallic beads on them. When the Grassi case is closed, the smaller convex bead of one ring loosely enters the concave bead of another ring, to form a seal at this zone and thus seal powder in the case.
More recent prior art is Kingsford U.S. Pat. No. 3,911,936, issued Oct. 14, 1975. According to that patent, the compact case is composed of resilient plastic, injection-molded elements. The patent states that the dies may be so accurately constructed as to provide inner and outer seals utilizing the resiliency of the parts alone.
Prior art patents relating to closures are the following: Marchant, U.S. Pat. No. 3,252,492, discloses a plastic bottle with a captive snap-on cap. Dahl, U.S. Pat. No. 4,060,173, discloses a container formed of a flexible sheet of resilient thermoplastic resin having a body section and a cover section which are hinged together, each having side and end walls which telescope together when closed. Davis, U.S. Pat. No. 4,298,133, discloses a foam plastic disposable tray and cover typically used for take-out dinners which are joined by an integral hinge along one edge. Tabs and undercut tab seats are formed in the tray and cover distant from the hinge to releasably latch the cover in a closed position on the tray.
Patents relating to hinge constructions are Dearth, U.S. Pat. No. 3,616,487; Wiesinger, U.S. Pat. No. 4,403,712; and Reuter, U.S. Pat. No. 4,407,427. The Dearth and Wiesinger patents both disclose flexible hinges of undulating or deformable rib constructions, while the patent to Reuter discloses a hinged construction where the cover of a waste container comprises a plurality of generally parallel ridges and grooves.